1. The aim of this study was to investigate the effects of a combined probiotic product (Lactobacillus paracasei, L. plantarum, and L. rhamnosus) on egg quality, sulphur compounds in manure and serum biochemistry of second cycle hens.

2. A total of 48 White Leghorn hens, at 52- to 54 weeks of age, were treated in a completely randomised design with water containing 0 or 1.8375 × 10¹⁰ cfu/l of probiotics for 8 weeks.

3. Probiotic supplementation did not affect egg quality. Albumen height and Haugh units were in general lowest in week 2 and highest in week 6.

4. For manure and serum parameters, water with or without probiotics produced statistically similar effects. An interacting trend for increasing concentrations of methyl mercaptan in manure was noted for probiotics x week, and should be further investigated. The week of supplementation significantly affected hydrogen sulphide, dimethyl sulphide, and triglycerides.

1. 本研究的目的是研究复合益生菌产品（副干酪乳杆菌、植物乳杆菌和鼠李糖乳杆菌）对第二轮母鸡的蛋品质、粪便中的硫化合物和血清生化的影响。

2. 总共 48 只 52 至 54 周龄的 White Leghorn 母鸡在完全随机的设计中用含有 0 或 1.8375 × 10 ¹⁰ cfu/l 益生菌的水处理 8 周。

3.补充益生菌不影响鸡蛋质量。蛋白高度和 Haugh 单位一般在第 2 周最低，在第 6 周最高。

4. 对于粪便和血清参数，添加或不添加益生菌的水产生的统计学上相似的效果。对于益生菌 x 周，注意到粪便中甲硫醇浓度增加的相互作用趋势，应进一步研究。补充周显着影响硫化氢、二甲基硫化物和甘油三酯。